Plant growth stimulants tend to be based primarily on phytohormones known as auxins and cytokinins.

Products like Dyna-Gro K-L-N and SuperThive contain synthetic analogs of nautral auxins. They are quite effective when fresh, but they degrade fairly rapidly if kept at room temperature or higher, or are exposed to light. That is why we no longer carry them. Instead, we are very proud to carry KelpMax Premium Seaweek Concentrate, which is not only more effective, but it has a shelf life of several years.

The benefits of the use of kelp in horticulture has been known for a very long time. In addition to fish, the Native Americans taught the Pilgrims to till kelp into the soil for better crop growth. A few decades ago, when kelp products were first offered to the grower, very little was known of their modes of action and many claims were made, some unjustified as well as based on incorrect assumptions. One clear finding was that when applied at specific times and in specific ways, some products triggered physiological responses in crops.

Back then, kelp products suffered from a poor reputation due to their inconsistency and confusing claims. As the decades passed new products were developed and greater science was applied to unlocking the truth behind their applications.

It is now known that the effects of kelp products can be explained by the presence of groups of plant hormones, namely auxins, cytokinins, and gibberellins. Some will tell you of the theory of the “illicitor effect” in which the kelp application triggers responses on a cellular level, for example stimulating enzyme production or certain defense mechanisms. It is now known that not only is the mere presence of these hormones important, but also that differences in the ratios of the various groups will affect the response. For example,a product with a high auxin content and a high cytokinin content might cause an auxin-like response in one crop but cytokinin response in another. If on the other hand the ratio of auxin to cytokinin is high – even if their overall levels are low – an auxin-like response will be triggered in almost all plants.

Seaweed-based products are quite variable, depending upon the species of kelp used, how they are harvested, and how the active ingredients are extracted from them. Among all kelps, as many as eight natural auxins and 16 natural cytokinins have been identified.

Structurally, kelp is made up of very tough cell walls that are resistant to rupture. In order to achieve breakdown of the cells to collect their contents most manufacturers use chemical or heat digestive processes, which leads to rapid degradation of the auxins, resulting in commercial products high in cytokinins. Our kelp concentrate, on the other hand, is produced using a patented high pressure differential technique that results in cellular burst, avoiding the use of chemicals, heat, freezing, or dehydration. That ensures extended hormone stability and a product high in auxins. In fact, if kept tightly sealed between uses, cool, and out of sunlight, the product will be usable for at least two years, which is considerably greater than liquid synthetic hormone products on the market.

So how does it work? Simply, this auxin-dominated extract stimulates prolific adventitious, and branching root formation. That drastic increase in root tip growth leads to an increased level of cytokinins in the treated plants, as that group of hormones is primarily produced in root tips. The increased root volume and number of root tips also increases moisture and nutrient uptake. The improve nutrient status, together with the higher levels of natural, internally-produced cytokinins in the plant, gives stronger top growth, making the plant more resistant to stresses such as drought, waterlogging, nutrient deficiency, or salinity, and some soil borne diseases. (There is a more-detailed explanation below, if you’re interested._

Seaweed extracts that are higher in cytokinins will also stimulate plant growth, but primarily in the top growth and not roots, so may lead to plants whose root systems are not developed enough to adequately support them. The result is a bigger, faster-growing plant, but one that can be weaker, and more susceptible to any number of stresses.